Chair frame



FIG. 1 is a front perspective view of a chair frame showing my new design;

FIG. 2 is a right side elevational view, the left side being a mirror image thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a front elevation view thereof.

FIGS. 2 through 4 have been drawn on an enlarged scale with respect to FIG. 1. 

The ornamental design for a chair frame, as shown and described. 